α-tocopherol succinate, but not α- tocopherol or other vitamin E analogs, stimulates prolactin release from rat anterior pituitary cells in vitro
Badamchian,M., Spangelo, BL., Hagiwara,Y., Hagiwara,H., Ueyama,H., Goldstein, GL. Nutritional Biochem. 6:340-344, 1995.
Background: Previous studies from this same group indicated that green barley leaves contained a form of Vitamin E (α-tocopherol succinate) that was effective in releasing the hormone prolactin and growth hormone from the rat pituitary, an important regulatory gland found in the brain. Prolactin is best known for its function in stimulating the production of breast milk, but it is also important for immune regulation and as both a growth factor and a factor which controls the rate of cell growth.
Lab Studies: These were cell culture studies and the researchers looked at the ability of various substances to increase prolactin release from the cells. Some of the substances (e.g. Thyroid Releasing Hormone, TRH) are known to increase prolactin release while other substances used were similar in chemical structure to α-tocopherol succinate. The idea was to compare all these different substances and see if the α-tocopherol succinate was more or less efficient at releasing prolactin. Another goal of the studies was to see if the researchers could determine how the α-tocopherol succinate was functioning to release the prolactin.
Conclusions: Only α-tocopherol succinate was able to increase the release of prolactin for the pituitary cells—none of the chemically similar substances were able to do this. In addition, the study was able to show that α-tocopherol succinate increases the release of prolactin by an unknown mechanism but that it was able to function along with TRH to increase prolactin secretion in greater amounts than either could on their own.